1. Field of the Invention
The present invention relates to a copying machine which provides a control device for controlling the lighting of blank lamps for removing charges from a non-used area of a photoconductor included in the copying machine.
2. Description of the Related Art
The inventors of the present invention know an electrostatic type copying machine which is constructed to, for processing a non-used area of a photoconductor in reduction copying or frame-eliminating copying operation, provide a plurality of blank lamps such as an LED (Light Emitting Diode) lamps between an exposing device and a developing bath and around the photoconductor included in the electrostatic type copying machine so that those blank lamps enable to remove the charges charged on a non-used area, that is, an out-of-image area of the photoconductor.
For the purpose of controlling the blank lamps to be lit on or off, the known electrostatic type copying machine is constructed to take the steps of sending control data from a control unit to a serial-to-parallel converting IC (Integrated Circuit) in a time-sharing manner, converting the control data which are serial data, into parallel data in the serial-to-parallel converting IC, outputting the converted data, that is, the parallel data, and controlling the number of the blank lamps to be lit according to the parallel data. As to one serial-to-parallel converting IC, for example, one 8-bit serial-to-parallel converting IC allows eight blank lamps to be controlled.
The aforementioned known copying machine, however, entails the serial-to-parallel converting IC for converting the serial data sent from the control unit into the parallel data.
The known copying machine also needs a long time for processing the control data, because it has to take the steps of sending the control data for controlling the lighting of the plurality of blank lamps to the serial-to-parallel converting IC in a time sharing manner and converting the serial data into the parallel data.
Moreover, a serial-to-parallel converting unit such as the serial-to-parallel converting IC of the known copying machine is likely to erroneously operate because of the adverse effect resulting from noises of a high-voltage photoconductor or the like.